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Steady Sleep Schedule May Help Keep Weight Off

Women who go to bed and wake up at regular times tend to maintain a healthy weight, a new study suggests.

Research has shown that not sleeping enough can have an effect on weight, but this new study from Brigham Young University finds that consistency in sleeping times can influence body fat.

“The message of this study seems fairly straightforward: Sleeping well consistently is associated with lower body fat in young women,” said Dr. David Katz, director of the Yale University Prevention Research Center. Katz was not involved with the study.

The study also suggested that better sleep — characterized by its efficiency, consistency and duration — is associated with more routine physical activity, he said.

“Some of the advantage in body composition from better sleep appears to be the effect of sleep itself, while some may be a product of more activity, ” Katz said. “It may also be that exercise facilitates better sleep, or vice versa.”

Katz cautioned, however, that this study did not prove a cause-and-effect relationship between sleep and weight.

The report was published online in the November issue of the American Journal of Health Promotion.

For the study, a team lead by exercise science expert Bruce Bailey collected data on 330 college women. Over a weeklong period, those who slept and woke at consistent times maintained a healthier weight.

Those who went to bed and woke up at or around the same time each day had lower body fat. Those who slept between eight and eight and a half hours had the lowest body fat, the researchers found.

Those whose sleep patterns varied more than 90 minutes had higher body fat than those whose sleep patterns varied less than 60 minutes, the researchers found.